| Message ID | 20220111081647.637752-1-jiasheng@iscas.ac.cn |
|---|---|
| State | New |
| Headers | show |
| Series | tty: serial: samsung_tty: Check null pointer after calling of_match_node | expand |
On 11/01/2022 09:16, Jiasheng Jiang wrote: > If there is no suitable node, of_match_node() will return NULL pointer. NAK. This is not possible. All drivers have such pattern and it was discouraged to add empty/dead NULL checks. If you think returning NULL is possible, please explain/document it. > Therefore it should be better to check it in order to avoid the > dereference of NULL pointer. > And the only caller s3c24xx_serial_probe() has already checked the > return value of the s3c24xx_get_driver_data(). > So the new check can be dealed with. > Best regards, Krzysztof
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c index e2f49863e9c2..efbf9a7d5e92 100644 --- a/drivers/tty/serial/samsung_tty.c +++ b/drivers/tty/serial/samsung_tty.c @@ -2185,6 +2185,9 @@ s3c24xx_get_driver_data(struct platform_device *pdev) const struct of_device_id *match; match = of_match_node(s3c24xx_uart_dt_match, pdev->dev.of_node); + if (!match) + return NULL; + return (struct s3c24xx_serial_drv_data *)match->data; } #endif
If there is no suitable node, of_match_node() will return NULL pointer. Therefore it should be better to check it in order to avoid the dereference of NULL pointer. And the only caller s3c24xx_serial_probe() has already checked the return value of the s3c24xx_get_driver_data(). So the new check can be dealed with. Fixes: 55ed51fff224 ("{tty: serial, nand: onenand}: samsung: rename to fix build warning") Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn> --- drivers/tty/serial/samsung_tty.c | 3 +++ 1 file changed, 3 insertions(+)